I have a 2006 ford crown vic police interceptor with 134k miles, over the past week or so on my way around town or to and from work, i noticed an interesting noise from the right rear of the vehicle. At first the noise started when i was getting on the highway; building up speed at about 45-55 MPH, then once i was maintaining 60, it would usually go away for that trip, initially I thought it was just interior plastic or something vibrating since it sounded like a rapid vibration kind of noise. Then one day i thought i'd roll down the window to see if i could hear it better, and i sure could. I recorded a few videos over 2 days; In this video, i am building up speed on an onramp, and as i pass under the overpass, you can really hear the clicking kind of noise, it almost sounds like a engine knock sound, but it is clearly coming from the right rear side of the vehicle, & the engine runs fine; no noise at idle, or when vehicle is parked. This video i am maintaining ~ 60 MPH, and the noise comes back but i have my window rolled up. Again you can clearly hear the clicking/ ticking vibrating noise from the right rear, then it stops at the 0:13 timestamp and it did not do it again for that trip, or the rest of the day. Fast forward a few days to today and once again i notice it on the highway, and when i'm going 20-30 mph on a town road and now it is more frequent, but still happens at total random times. Here we are going about 25 mph and you can hear the sound slower but it's the same similar sound, but it just starts at random and stops whenever, if you break it doesn't stop, it doesn't happen if i go over bumps or anything like that. I have heard sounds of failing wheel bearings and it doesn't sound like that to me, i have jacked the car up and shook the wheels for play both up/down and left/right and they feel solid, without play.
Thank you for taking your time to read this.
All videos uploaded to imgur at: https://imgur.com/gallery/HaNidNR
I've run into a similar problem a couple times .Now that cars have a dozen heat shields and plastic panels for aerodynamics on their underside, that's the first place I would look. If anything is knocked or wears loose, it will flap or resonate at odd speeds.
@glen_stet This car is so old school it doesn't have many heat shields on the underside as many newer cars do. i looked underneath and nothing seems loose, i jacked the wheel up and checked for any sort of play and there was none, there was a slight noise when i spun it that sounded like it could be abnormal, the other side didn't make it much or at all really, but it was so miniscule.
Emissions EVAP systems often make weird, noises at various times. Is it located where its activities could create your sound?
I had same issue on my 97' subaru outback ( other car is 2000 crown vic lx) I haven't had problems with this on vic but on subi the parking brake uses brake shoes & its behind the rear rotors. The p. brake was so rusty / falling apart that there was metal 2 metal contact intermittently just like your vid. shows.
